Diabetes is a group of metabolic diseases in which a person has high blood sugar, either because the pancreas does not produce enough insulin, or because cells do not respond to the insulin that is produced. Diabetes is widely recognized as a leading cause of death and disability throughout the world, and the number of people diagnosed with diabetes mellitus is expected to increase dramatically in the next few decades. Diabetes management can involve changes in diet and/or use of insulin to maintain normal blood sugar levels.